Project Summary Physical activity (PA) is key to both preventing childhood obesity and reducing an individual's risk for certain types of cancer. While conventional PA interventions (e.g., exercise, health clubs) face problems of sustained motivation and adherence to fitness or training programs, active video games (AVGs) offer an innovative alternative for PA promotion due to their promising motivational properties. Although studies suggest that AVGs allow players to achieve the recommended levels of PA, children's motivation to play AVGs often decreases quickly. To reduce this decline, our study introduces an innovative motivating factor: a narrative. A narrative or storyline effectively draws on the human need for narrative closure (i.e., the need to find out how the story will end). A well-constructed narrative has a significant impact on cognition, affect, and health behavior. However, narrative elements are seldom incorporated into AVGs. An AVG with a storyline should encourage children to engage in more PA through increased motivation and extended play. Consequently, AVGs with compelling narratives should increase players' activity energy expenditure (AEE), PA level, and heart rate. Moreover, AVGs with narratives are likely to be more interactive, immersive, and engaging, and thereby elicit cognitive, affective, and behavioral experiences that differ both quantitatively and qualitatively from those elicited by nonnarrative AVGs. The proposed study explores both the novel addition of a compelling narrative to AVGs and its psychological and behavioral consequences on PA. It proposes to create corresponding narrative and nonnarrative cutscenes of comparable duration interspersed in an existing AVG; 40 children aged 8 to 11 will play narrative or nonnarrative versions of the games by watching corresponding cutscenes (i.e., brief, animated clips played in video games) and playing the game. Their cognitive and affective evaluation, motivation to play the games, duration of play, activity energy expenditure (AEE), PA level, and heart rate will be measured for the narrative and nonnarrative versions of the AVG. This study is a first step in a series of rigorous systematic inquiries into the behavioral potentials of narratives via AVGs for combating childhood obesity. The exploration of a narrative's motivating capacity in AVGs will inspire novel AVG designs and introduce a new dimension of PA facilitation among children with immersive and involving games, which may then be translated into school- or family-based health media interventions. Such inquiries would help to create innovative and effective media products to be applied to various health interventions.